Multiple forms of alkaline and acid phosphatases in rat tissues in the postnatal period

1. A new open-circuit respiratory method was developed to estimate mixed venous PCO2 more rapidly and accurately than is possible with rebreathing techniques. 2. The subject breathes a mixture of CO2 in air from an open circuit. Carbon dioxide is added to the air flowing through the circuit at a rate such that the PCO2 in the inspired and expired gases (recorded continuously with a CO2 analyser) are almost identical. 3. Results from respiratory and cardiac patients showed that equilibrium occurred in less than 10 s. There was good agreement between the tensions of CO2 in the respiratory plateaux and in mixed venous and arterial blood withdrawn during equilibrium. 4. During exercise, the tensions of CO2 of the plateaux and arterial blood at equilibrium also showed good agreement. 5. It is suggested that the new method represents an improvement over rebreathing methods as equilibrium is achieved rapidly before the mixed venous tension rises from recirculation.     

Lipid composition of hepatic and adipose tissues from normal cats and from cats with idiopathic hepatic lipidosis

Physical restraints are a frequently used but disputed method to prevent falls. The aim of the present study was to investigate how the use of restraints in institutional elder care relates to previous falls and to the estimated fall risk of the individual patient. A total of 1142 patients, mean age 82 years, were included in the study. A questionnaire, the Multi-Dimensional Dementia Assessment Scale (MDDAS), was used to measure motor function, vision, hearing, ADL performance, behavioral symptoms, psychiatric symptoms, cognitive impairment and use of medication. Questions concerning the use of physical restraints and known previous falls were added to the instrument. Based on data from the questionnaire (MDDAS), a score on the Downton Fall Risk Index was calculated for each patient. All in all, 248 (22%) of the patients had been subject to restraints and for 155 of them (14%) such measures had been taken to prevent falls. Only weak connections were found between the restraining of patients to prevent falls and the prevalence of known previous falls during hospital stay (phi = 0.05), and estimated fall risk (phi = 0.07). The results indicate that the use of physical restraints is poorly connected with the estimated fall risk. Therefore, this study may point to a possible overuse of these measures.     

Choline acetyltransferase in ocular tissues of rabbits, cats, cattle, and man

The variation of choline acetyltransferase activity in ocular tissues of four mammalian species, rabbits, cats, cattle, and man, was determined. Enzyme activity of irides and ciliary bodies, i.e., parasympathetically innervated structures, tended to be similar in all four species. Two exceptions were bovine irides and human ciliary bodies; these two tissues had higher enzyme activities. Choline acetyltransferase activity was present in the corneal epithelium of rabbit, bovine, and human eyes, but little or none could be detected in that of cats. Feline retina and pigment epithelium-choroid also contained far less choline acetyltransferase activity than the same tissues in the other three species.     

Variability of choline acetyltransferase in ocular tissues of rabbits, cats, cattle and humans

It has been proved in three rodent species that in the insoluble collagen fraction which accumulates in skin collagen with age of the two categories of collagen present (collagen type I and collagen type III), their proportion alters in favour of collagen type I with the advancing age. Since it has also been shown that collagen type I is less resistant towards proteolytic cleavage than is collagen type III its accumulation can be explained either by rapidly advancing cross-linking of this collagen type or more likely by different proteosynthesis. The second alternative is preferred since a step-wise polymerization of collagen type III was also observed. No information revealing to what extent the lysine derived cross-links can combine both collagen types is at present available. On the basis of this information the rapid decrease in insoluble collagen in very early ontogeny (rats below 8 weeks of age) is explained.     

Sequence analysis of the putative viral enhancer in tissues from 33 cats with various feline leukemia virus-related diseases

INTRODUCTION: The incidence of shigellosis in Israel was fairly stable until around 1974, when it gradually began to increase to a peak in 1985. This was accompanied by a shift in the maximum incidence in the Jewish population from the age group < 1 to 1-4 years. AIM: To update the epidemiology of shigellosis in Israel 1986-1995. METHODS: Only laboratory-confirmed cases of shigellosis in the civilian population were analyzed. Data were obtained from the weekly reports of the subdistricts. Antibiotic sensitivity data were obtained from several hospitals and the General Workers' Sick Fund laboratories in Jerusalem, Haifa, and Tel Aviv. RESULTS: From 1986 to 1991, shigellosis incidence per 100,000 decreased by about 50%, and the decrease occurred mainly in the Jewish population. Several regional outbreaks in 1992 reversed this decline, but by 1995, the incidence was similar to that observed prior to 1974. The disease still occurs mainly in the summer, with an occasional winter outbreak. Higher incidence rates occurred in the northern subdistricts. The peak incidence in the non-Jewish population moved from the < 1-year-olds to the 1-4 year-old group, similar to the pattern in the Jewish population in 1970. In 1991, for the first time, the rate in the age group 5-9 years among non-Jews exceeded that of those < 1 year old. Marked decreases in sensitivity to several antibiotics were found in peripheral and hospital laboratories. An increase in the sensitivity to tetracycline was noted since 1991. Case fatality rates remain low, with a mean of 0.05% for the decade of the 1980s. CONCLUSIONS: Shigellosis remains a highly endemic disease in Israel, but changes in the age-related peak incidence indicate that the pattern of spread is becoming more similar to other developed countries.     

Protein tyrosine phosphatases in cell transformation

The role of tyrosine phosphorylation in cell transformation has been well established. It has been proposed that protein tyrosine phosphatases (PTPases) may be capable of dephosphorylating critical substrates involved in the transformation process, suggesting that they represent a tumor suppressor family of enzymes. Indeed, recent work showed that overexpression of some PTPases in malignant cells counteracted the action of oncogenic tyrosine kinases although overexpression of other forms of these enzymes increased tumorigenicity. The work described herein has provided some insight into the action, both antagonistic and synergistic, of the kinases and phosphatases on cell growth and transformation.     

Purification and characterization of ceramide-activated protein phosphatases

Ceramide has emerged as a potential regulator of diverse cellular functions, and a few direct targets have been identified for its action including protein kinases and phosphatases. In this study, we have purified the predominant ceramide-activated protein phosphatase (CAPP) from rat brain. Utilizing a novel chromatographic approach, CAPP was purified to near homogeneity using hydrophobic interaction chromatography on phenyl Sepharose followed by anion-exchange chromatography on MonoQ. The purified protein was composed of three major bands on SDS-polyacrylamide gel electrophoresis which comigrated with the three subunits of heterotrimeric PP2A. Immunologic studies further identified CAPP to be composed predominantly of heterotrimeric AB'C and ABalphaC as well as heterodimeric PP2A (AC), where C is the catalytic subunit, and A and B are regulatory subunits. These results were also supported by the coelution of CAPP with trimeric and dimeric PP2A on size-exclusion chromatography. These studies provide a convenient and efficient method for the isolation of trimeric and dimeric PP2A, and they allow the biochemical investigation of CAPP.     

Social interactions in cats: regional brain monoamine distribution in dominant and submissive cats

Immunological memory has been ascribed to the presence of long-lived memory cells. The mechanisms underlying their generation are not completely understood, but dependence on antigen persistence has been discussed in this regard. However, in spite of in vivo evidence favoring this model, studies on TCR/CD3 stimulation of T cell lines or unseparated peripheral blood T cell in vitro have failed to demonstrate prolonged survival of preactivated cells. We have examined the dose-dependent effect of TCR/CD3 engagement mimicked by immobilized anti-CD3 antibody. To this end, well-defined populations of CD4+ and CD8+ lymphoblasts isolated from bulk cultures of preactivated PBMCs by flow sorting were examined. These cells were restimulated with immobilized anti-CD3 in the presence or absence of various costimulatory factors, and were analyzed for their viability state, as well as their apoptotic and proliferative behavior. We have shown that inhibition of apoptosis following CD3 stimulation occurs at submitogenic concentrations, while activation-driven apoptosis requires high-density TCR/CD3 activation. Prevention of apoptosis by submitogenic CD3 stimulation was, however, observed only when CD4+ but not when CD8+ cells were investigated, and was not readily influenced by other costimulatory factors present in cultures. This observation points to the importance of antigen persistence in regulating survival of memory CD4+ but not CD8+ cells.     

Grooming behavior in cats with pontile lesions and cats with tectal lesions.

Because an abnormal grooming behavior that is mediated by the superior colliculi is elicited from cats with pontile lesions, an ablation study of these structures was conducted in 40 cats to specify quantitatively the changes in grooming behavior. Ss that underwent the surgical procedure except for the lesion and Ss with lesions of the auditory and visual cortices served as controls. Time-lapse motion pictures of the Ss in their home cages were taken, and statistical analyses of the grooming behavior shown on the films indicated that Ss with pontile lesions and those with tectal lesions spent less time grooming, had shorter grooming bouts, and failed to exhibit the normal temporal pattern of grooming behaviors. Other studies revealed that Ss with pontile or tectal lesions were deficient in removing tapes stuck on their fur. A sensory-loss hypothesis appeared to account for some of the changes, but a deficit in endogenous control of the grooming behaviors also was indicated. The literature on grooming behavior related to peripheral vs endogenous control is reviewed, and the role of the superior colliculi as a higher order integrative center for complex behaviors is emphasized. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acid and alkaline phosphatases in the kidney of a few fishes

The localization of acid and alkaline phosphatases in the kidney of Cirrhinus reba, Ompak bimaculatus and Labeo gonius has been studied. In all these fishes, the enzymes are found in the proximal tubule. The activity of alkaline phosphatase is more stronger than acid phosphatase. The renal capsule, distal tubule, collecting tubule and interstitial hematopoietec tissue are all phosphatase negative. The activity is more stronger in the first proximal tubule than in the second tubule. It is probable that acid phosphatase is associated with the intracellular digestion of the macromolecules absorbed and alkaline phosphatase with the absorption of glucose from the tubular lumen.     

Feline immunoglobulin E: induction of antigen-specific antibody in normal cats and levels in spontaneously allergic cats

A number of lines of evidence suggest that immunotherapy with the cytokine interleukin-2 (IL-2) may boost the immune system to fight tumors. CD4+ T cells, the cells that orchestrate the immune response, use these cytokines as signaling mechanisms for immune-response stimulation as well as lymphocyte stimulation, growth, and differentiation. Because tumor cells begin as 'self', the immune system may not respond in an effective way to eradicate them. Adoptive cellular immunotherapy can potentially restore or enhance these effects. We illustrate through mathematical modeling the dynamics between tumor cells, immune-effector cells, and IL-2. These efforts are able to explain both short tumor oscillations in tumor sizes as well as long-term tumor relapse. We then explore the effects of adoptive cellular immunotherapy on the model and describe under what circumstances the tumor can be eliminated.     

Protein phosphatases and the regulation of MAP kinase activity

A family with hereditary factor X deficiency is presented. One member, a 25-year-old man, showed a mild bleeding tendency. His factor X activity (extrinsic: 56%; intrinsic: 55%; Russell's viper venom: 57%) and his level of circulating factor X antigen (55% of normal) were markedly reduced. Analysis of his factor X gene revealed a single point mutation within exon II resulting in the substitution of +25 Gla (GAA) by Lys (AAA). The mutation was determined by gene analysis to be heterozygous in this patient, his mother and one of his brothers. Clotting assays of factor X purified from the plasma of the index patient revealed an activity of 89% of normal upon activation with Russell's viper venom, 77% of normal in the intrinsic and 81% of normal in the extrinsic coagulation pathway. The mutation responsible for the substitution of Lys for Gla+25 was introduced into an expression plasmid containing a wild type factor X cDNA and expressed in a mammalian cell line. Factor X antigen levels in the cell lysates and in the supernatant were identical in the mutant and wild type constructs. The specific activity of the factor X expressed from the mutant construct was 3% compared with the wild type construct. These data demonstrate that the substitution of Lys for Gla+25 results not only in a reduced level of factor X in the affected family members, but also in a substantial loss of specific factor X activity.